This invention relates to vacuum packaging arrangement, and more particularly to a combination support member and vacuum manifold for use in a vacuum packaging arrangement.
A typical vacuum packaging machine includes a series of components that move in a circular path about a central hub area. A series of radially spaced plates rotate about the central hub area, and each plate is adapted to support a package that is to be evacuated. A series of vacuum chambers or heads also rotate about the central hub area, and each vacuum chamber is located above one of the plates. The plates are movable between a loading area and a discharge area. During movement of the plates from the loading area to the discharge area, the vacuum chambers are sequentially lowered onto the plates to evacuate the packages, and then raised off the plates after the packages have been evacuated and sealed.
In this type of system, each vacuum chamber is mounted to the outer end of an arm, which has an inner end that is mounted at the central hub area. A cylinder or the like is secured to the inner end of each arm, and selectively raises and lowers the arm for moving the vacuum chamber between the raised position and the lowered position. Vacuum is supplied to the interior of the chamber from a central vacuum source through a hose that extends from the central hub area of the machine, along the arm, and is connected at an outer end to the vacuum chamber.
It can thus be appreciated that prior art vacuum packaging machines of this type involve a relatively complex mechanism for simultaneously rotating the plates and the vacuum chambers, and for raising and lowering the vacuum chambers at predetermined locations in the path of movement of the plates. In addition, the long hose length between the vacuum source and the vacuum chambers results in relatively slow vacuum actuation, in that a significant amount of air must be moved from the vacuum chamber and the hose before vacuum is actually supplied to the interior of the vacuum chamber.
It is an object of the present invention to provide a vacuum packaging machine which simplifies movement of the vacuum chambers toward and away from the surfaces that support the packages to be evacuated. It is a further object of the invention to provide such a vacuum packaging machine which avoids the rotary, circular motion of prior art machines and simplifies the motion by which the vacuum chambers are moved into contact with the surfaces that support the packages to be evacuated. A still further object of the present invention is to provide such a vacuum packaging machine which significantly reduces the amount of air to be moved when the vacuum is to be supplied to the vacuum chambers, to accelerate the evacuation process and to shorten the vacuum cycle. A still further object of the present invention is to provide such a vacuum packaging machine which provides linear, reciprocating motion of the vacuum chambers together by means of a vacuum manifold to which the vacuum chambers are mounted.
In accordance with one aspect of the invention, a vacuum packaging system includes a movable support and vacuum manifold having an interior connected to a vacuum source, and a series of evacuation chambers carried by the support member and vacuum manifold and in communication with the interior of the movable support and vacuum manifold. The vacuum packaging system also includes a package advancement arrangement that includes a series of package supports positioned below the series of evacuation chambers. The movable support and vacuum manifold is movable between a first position and a second position. In the first position, the movable support and vacuum manifold is operable to place the evacuation chambers in an operative position in which each evacuation chamber is engaged with a package support to evacuate a package contained therein. In the second position, the movable support and vacuum manifold is operable to place the evacuation chambers in an inoperative position in which the evacuation chambers are spaced from the package supports. In one form, the combination support member and vacuum manifold is connected to a first linearly reciprocating mechanism for sequentially moving the one or more evacuation chambers between the operative and inoperative positions. The product supports, which may be in the form of a series of platens, are movable in an upstream to downstream direction below the vacuum chambers. The combination support member and vacuum manifold is further connected to a second linearly reciprocating mechanism for sequentially moving the evacuation chambers between an upstream position and a downstream position along with the platens while the evacuation chambers are in the operative position in engagement with the platens. In this manner, the package evacuation occurs while the vacuum chambers and platens are being advanced. After the vacuum chambers are disengaged from the platens that contain the evacuated packages, the vacuum chambers are subsequently positioned over an adjacent set of platens as the combination support member and vacuum manifold is moved in the downstream-to-upstream direction.
In one embodiment, the combination support member and vacuum manifold is in the form of an elongated beam member to which the series of vacuum chambers are secured, and the interior of the combination support member and vacuum manifold is in the form of an internal cavity defined by the elongated beam member. The elongated beam member is secured to a carriage, and the carriage is interconnected with the first and second linearly reciprocating mechanisms for moving the vacuum chambers between the operative and inoperative positions and for moving the evacuation chambers in the upstream and downstream directions. Representatively, a vacuum valve mounted to the elongated beam member in the vicinity of each vacuum chamber, and a vacuum communication conduit is connected between each vacuum valve and each vacuum chamber. Each vacuum valve is selectively movable between an open position for communicating vacuum from the internal cavity of the elongated beam member to the vacuum chamber through the vacuum communication conduit, and a closed position to cut off the supply of vacuum to the vacuum chamber through the vacuum communication conduit.
The invention also contemplates a method of operating a vacuum packaging machine, and a support arrangement for vacuum supply members in a vacuum packaging machine, substantially in accordance with the foregoing summary.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.